I have been looking over v12beta4, but needed hash tables in a bit of the code I am using. I did not find them in the release, so wrote something I thought reasonable.
Perhaps the enclosed will encourage one of your students to do better.
Good to finally see the new version of Gambit!! Thanks much!
Nice to hear from you. Coincidentally I've been working on an efficient implementation of tables for the past 3 weeks. I'm using hash tables and open addressing, double hashing, autoresizing, and support weak keys and/or weak values. All of this will be in beta 13. Note that object->serial-number is currently implemented with association lists. I'll use tables (with weak keys) when they are fully debugged.
Marc